Rfid disruption device and related methods

ABSTRACT

Devices and methods of disrupting data transfer between an RFID interrogation device ( 50, 50 ′) and an RFID data storage device ( 30, 30 ′) to be protected, are provided. An example of an embodiment of an RFID signal disruptor device includes a container ( 41, 141 ) and an RFID signal disruptor circuit ( 151, 161, 161′, 171, 171′, 271, 271 ′) configured to substantially disrupt the signal provided by the RFID interrogation device ( 50, 50 ′) when the RFID signal disruptor device is positioned to protect the RFID data storage device ( 30, 30 ′). The RFID signal disruptor device can also include an interrogation indicator ( 63, 296 ) configured to indicate to a user of the RFID data storage device ( 30, 30 ′) that an unauthorized RFID interrogation device ( 50, 50 ′) is attempting to interrogate the RFID data storage device ( 30, 30 ′) when the RFID signal disruptor device is positioned in close proximity to the RFID data storage device ( 30, 30 ′) to provide protection thereto and when the RFID interrogation device ( 50, 50 ′) is producing the interrogation signal.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.14/785,583 which is a 35 U.S.C. 371 National Stage of InternationalApplication No. PCT/US2013/040636, titled “RFID DISRUPTION DEVICE ANDRELATED METHODS,” filed on May 10, 2013, which claims priority to U.S.Provisional Application No. 61/817,686, titled “RFID DISRUPTION DEVICEAND RELATED METHODS,” filed on Apr. 30, 2013, and to U.S. ProvisionalApplication No. 61/814,124, titled “RFID DISRUPTION DEVICE AND RELATEDMETHODS,” filed on April 19, 2013, all of which are incorporated byreference herein in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of contactless circuitry and,more particularly, to Radio Frequency Identification (“RFID”) devicesand methods related to prevent the unauthorized interrogation andtracking thereof.

2. Description of Related Art

Theft of credit or debit card information and identification has becomerampant worldwide. Governments, companies, and consumers spend millionsof dollars each year to prevent and pursue such thefts.

Over the years, various types of identification technology have beenused for credit or debit cards and for identification. These, forexample, have included pin numbers, bar codes, and magnetic strips. Morerecently, however, steps have been taken to use RFID or othercontactless chip technology in association with credit or debit cards,passports, documents, and other areas where identification, includingportable and remote, are desired. An example of such applications ofRFID can be seen in a recent news article titled “Contactless Traveling”by Wright (Electronic Design News (EDN) Jul. 7, 2005) for passportapplications.

Other types of uses of RFID have emerged, not necessarily coincidingwith the desires of the owner of the RFID device. For example, someretailers have instituted what can only be considered inappropriatetracking of the RFID device users in order to analyze their buyinghabits. Such tracking ability may provide government agencies an abilityto continually track an individual's movements. Although appearingsomewhat futuristic, it would appear that various governments arecurrently spending billions of dollars for data mining operation centersto collect data on various commercial transactions. Eventually they mayembed RFID tags into all required government documents. Variousgovernment agencies would know this and could use the various trackingtechniques to track of any individual's movements by pinging theindividual's RFID device at opportune locations with RFID interrogationdevices or other forms of RFID readers.

The recent developments in technology do not fully address potentialsecurity breaches of the RFID such as when an unauthorized RFIDinterrogation or reading device attempts to extract the RFID informationor track the RFID device, especially when a user or possessor of an RFIDdevice is unsuspecting or not cognizant that the RFID device is beinginterrogated.

Others have attempted solutions at creating blocking RFID devices toenhance privacy. Examples can be seen in U.S. Patent ApplicationPublication No. 2004/0222878 A1 by Juels titled “Low-ComplexityCryptographic Techniques For Use With Radio Frequency IdentificationDevices,” U.S. Pat. No. 6,970,070, by Juels, et al. titled “Method andApparatus For Selective Blocking of Radio Frequency IdentificationDevices,” and U.S. Pat. No. 7,298,243 by Juels, et al. titled “RadioFrequency Identification System With Privacy Policy Implementation Basedon Device Classification.” Such attempted solutions, however, do notprovide a protection capability that can be applied independent of theinformation contained in the RFID device to be protected, or thelocation of the device with respect to the external environment. Thatis, such devices generally either require a classification engine,require positioning in a designated privacy zone, require application ofa specified privacy policy, require knowledge of the identifier of thedevice to be protected, or require some form of information encryption.

Accordingly, there still exists a need for a simple, flexible, andpractical security and privacy protection solution for RFID and othercontactless circuitry or chip devices, which can prevent a transmissionfrom an RFID reader or scanner from activating an RFID device, which canprevent the reader from receiving readable data if activated, and whichcan indicate to the user when an RFID reader or scanner is attempting tointerrogate the user's RFID device. There also exists a need for asimple, flexible, and practical security and privacy protection solutionwhich can be restricted to functioning only when in close proximity tothe device to be protected, regardless of the location of the devicewith respect to the external environment, and that will not interferewith the operation of an RFID device reader or scanner when notpositioned in close proximity to the device to be protected.

Factors such as expense, size, practical and flexible use requirementsfor RFID and other contactless chip technology create problems andbarriers for widespread use in many applications. Accordingly, therefurther exists a need for a solution that provide users of RFID devicesincreased flexibility with little or no increase in expense or size, andyet effectively block or otherwise prevent unauthorized access to RFIDinformation associated with the RFID device to be protected.

SUMMARY OF THE INVENTION

In view of the foregoing, various embodiments of the present inventionadvantageously provide combinations, devices, and methods of enhancedRFID protection against unauthorized reading or interrogation of an RFIDdevice, which can prevent a transmission from a reader or scanner fromactivating an RFID device, which can prevent the reader from receivingreadable data if activated, and which can indicate to the user when anRFID reader or scanner is attempting to interrogate the user's RFIDdevice. Various embodiment of the present invention also advantageouslyinclude combinations, devices, and methods that can advantageouslyprovide users of RFID devices increased flexibility with little or noincrease in expense or size and yet effectively block unauthorizedaccess to RFID information associated with a device. Various embodimentsof the present invention also advantageously provide personal privacycountermeasures, not just in the form of data protection, but protectionof financial or other personal information and/or a unique indicator(e.g., credit/debit card account number, account ID, PIN, licensenumber, Social Security number, employee identification number, etc.)from being logged without the individual's knowledge. Variousembodiments of the present invention can perform such objectives bymaking the RFID device functionally invisible to the RFID reader whenthe RFID device is being protected.

An example of an embodiment of the present invention provides an RFIDsignal disruptor device to prevent data transfer between a nearby RFIDinterrogation device such as an RFID reader, and one or more RFID datastorage devices when the RFID signal disruptor device is adjacent theone or more RFID data storage devices interrogated therewith. The RFIDsignal disruptor device includes an RFID signal disruptor circuitpositioned or positionable in a container and configured to disrupt anattempted read of a separate RFID device by an RFID interrogation devicewhen the separate RFID device is positioned adjacent the signaldisruptor circuit to allow mutual inductive coupling therebetween. TheRFID signal disruptor device is configured to operatively receive powerneeded to operate the RFID signal disruptor circuit from aninterrogation signal emanating from the RFID interrogation device duringthe attempted read of the separate RFID device when mutually inductivelycoupled with the separate RFID device.

The signal disruptor circuit, for example, can include a transducerpositioned to receive portions of the RFID interrogation signal and toemanate a disruptive signal generated in response to the receivedportions of the RFID interrogation signal, and a high-speed switchoperably coupled to the transducer to provide for approximate signalsynchronization with the RFID interrogation signal to thereby generatethe disruptive signal having an insubstantial propagation delay. Thesignal descriptor circuit also can include a signal ringer including acurrent regulator coupled to the high-speed switch to extend a durationof the disruptive signal being generated, a voltage regulator operablycoupled to the high-speed switch and the current regulator to stabilizea base voltage of the high-speed switch, and/or a tunable frequencyregulator operably coupled to the high-speed switch to control frequencycharacteristics of the disruptive signal.

The signal disruptor circuit can also or alternatively include a voltagerectifier operably coupled to the high-speed switch and the transducerto maintain a DC current flowing within the RFID signal disruptorcircuit. According to an exemplary configuration, the voltage rectifieris a diode having an anode connected to a second end of the transducer(e.g., RFID antenna) and a cathode connected to a base or gate of thehigh-speed switch (e.g., single transistor/single stage transistorcircuit). The signal disruptor circuit can also or alternatively includea visual operation indicator coupled to the high-speed switch to providea visual indication that the RFID interrogation device is attempting tointerrogate the separate RFID data storage device when the RFID signaldisruptor circuit is positioned in close proximity to the separate RFIDdata storage device, sufficient to allow mutual inductive couplingtherebetween, when the RFID interrogation device is producing aninterrogation signal within activation range of the separate RFID datastorage device. According to an exemplary configuration, the voltagerectifier and the visual indication indicator part provided in a singlecomponent such as, for example, a light emitting diode or other similarcomponent/component circuit.

According to an exemplary configuration, the transducer includes an RFIDantenna, the high-speed switch includes a transistor and/or single stagetransistor circuit arrangement, and the signal ringer includes, forexample, one or more wound inductors positioned to cause a signaloscillation, thereby causing additional current to flow within the RFIDsignal disruptor circuit to extend the duration of the disruptivesignal. According to the exemplary configuration, the voltage regulatorincludes one or more resistors positioned to stabilize base voltage ofthe transistor to thereby provide for substantially consistent operationof the transistor over a range of voltages associated with the receivedRFID interrogation signal, and the tunable frequency regulator includesone or more varactor diodes positioned to provide for tuning theresonant frequency of the signal ringer and to provide harmonicmultiplication of the frequency of the interrogation signal.

According to the exemplary configuration, the RFID antenna also oralternatively has a planer-shaped coil, and the RFID signal disruptorcircuit can contain only a single transistor or single stage transistorcircuit arrangement to provide significantly less propagation delay thanthat resulting from multistage circuit configurations. According to theexemplary configuration or an alternative configuration, the inductor isconnected between the emitter of the transistor and a first end of theresistor, a second end of the resistor is connected to the base of thetransistor, and the RFID antenna is connected between the collector ofthe transistor and the second end of the resistor. According to theexemplary configuration or an alternative configuration variation havingan alternating current (AC) capacitor, the capacitor can be connectedbetween the first and the second ends of the resistor. According to theexemplary configuration or an alternative configuration, the varactordiode is connected between the base and the emitter of the transistor.

Advantageously, according to an exemplary configuration or analternative configuration, the RFID signal disruptor device is devoid ofany permanent power storage device (e.g., battery), and instead reliessolely on energy from the RFID interrogation signal to power the RFIDsignal disruptor circuit. This advantageously reduces the size, profile,and weight of the device thereby allowing ready application to a planershaped container, for example.

Another example of an embodiment of the RFID signal disruptor circuitincludes an antenna positioned to receive portions of the RFIDinterrogation signal and to emanate a disruptive signal, and atransistor defining a high-speed switch operably coupled to the antennato provide for approximate signal synchronization with the RFIDinterrogation signal to thereby generate the disruptive signal having aninsubstantial propagation delay therebetween. According to anembodiment, the antenna can be in the form of a planer-shaped coil isunderstood by one of ordinary skill in the art. According to anembodiment, in order to reduce propagation delay, power consumption, andweight of the device, the transistor can be a single transistor or firststage transistor circuit.

The circuit can also include a wound inductor (not a coiled antenna)coupled to the transistor and positioned in the RFID signal disruptorcircuit to cause a signal oscillation such as, for example, ringing,thereby causing additional current to flow within the RFID signaldisruptor circuit to thereby extend a duration of the disruptive signalbeing generated. The circuit can further include a resistor positionedwithin the RFID signal disruptor circuit to stabilize a base voltage ofthe transistor to thereby provide for substantially consistent operationof the transistor over a range of voltages associated with the receivedRFID interrogation signal.

According to an embodiment, the wound inductor can be connected betweenthe emitter of the transistor and a first end of the resistor, a secondend of the resistor is connected to the base of the transistor, and theantenna is connected between the collector of the transistor and thesecond end of the resistor, and then AC capacitor is connected betweenthe first and second ends of the resistor.

According to an embodiment, the circuit can also include a varactordiode operably coupled to the transistor to provide for tuning theresonant frequency of a signal ringer portion of the circuit and toprovide harmonic multiplication of the frequency of the interrogationsignal. The varactor diode can be connected between the base and theemitter of the transistor. The varactor diode can also be tunable.

According to an embodiment, the above described RFID signal disruptorcircuit is a first RFID signal disruptor circuit positioned within acontainer such as, for example, a plastic card or passport book or cardto form the RFID signal disruptor. According to another embodiment, theRFID signal disruptor can include a second RFID signal disruptor circuitpositioned within the same container. In this embodiment, the polarityof the transistor in the first circuit can be the opposite of that ofthe second circuit. For example, the first transistor is a bipolarjunction PNP transistor and the second transistor is a bipolar junctionNPN transistor. Note, other forms of transistors including field effecttransistors can be utilized as substitutes.

Another example of an embodiment of the RFID signal disruptor circuitincludes a first antenna configured to receive portions of the RFIDinterrogation signal, a second antenna configured to transmit adisruptive signal, a first transistor having a collector connected to afirst end of the second antenna, and a second transistor having acollector connected to a second end of the second antenna and an emitterconnected to an emitter of the first transistor. The circuit can alsoinclude a frequency modulator including a capacitor in parallel with adiode to provide a low-frequency ringing. According to an exemplaryconfiguration, the first end of the capacitor and the first end of thediode are operably coupled to a medial portion of the second antenna,and the second end of the capacitor and the second end of the diode isoperably coupled to the emitter of the first transistor and the emitterof the second transistor.

Another example of an embodiment of the present invention provides acombination of a separate RFID device and a separate RFID signal capturedevice each configured to be positioned separately into a container.More specifically, the combination includes a separate RFID devicecarrying and RFID transponder (tag) configured to be positioned in thecontainer and a separate RFID signal capture device configured to bepositioned adjacent the separate RFID device and in the container sothat when an unauthorized RFID interrogation device attempts tointerrogate the separate RFID device from within the container, theseparate RFID signal capture device positioned adjacent the separateRFID device blocks or otherwise prevents the attempted read, andconfigured so that when an authorized user desires to use the separateRFID device for an authorized read, the authorized user selectivelyremoves either the separate RFID device or the separate RFID signalcapture device from being adjacent each other and presents the separateRFID device for the authorized read.

Another example of an embodiment of a device to prevent unauthorizedRFID interrogation when the device is positioned adjacent a separateRFID device, includes an RFID signal capture device including anincoming signal detector configured to detect an incoming signalattempting to interrogate the separate RFID device responsive to thedetection of the incoming interrogation signal to respond to theincoming interrogation signal with disruptive read signals.

Another example of an embodiment of a device for preventing unauthorizedRFID interrogation when the device is positioned adjacent a separateRFID device, includes an RFID signal capture device including anincoming signal detector to detect incoming RFID interrogation signalsresponsive thereto, and an RFID interferer to interfere with activationof operation ability of the separate RFID device responsive to theincoming signal detector.

Another example of an embodiment of a device to prevent unauthorizedRFID interrogation includes an RFID signal capture device that workswith the RF carrier of the tag/transponder circuit of an RFID device tobe protected using any standard modulation or data protocol, such as,for example, amplitude shift keying (ASK), frequency shift keying (FSK),or phase shift keying (PSK), among others as understood by those skilledin the art Advantageously, the RFID signal capture device, according tothis exemplary embodiment, does not directly emit or radiate signals,but rather, only captures the signal from the tag and disrupts thenormal operation of the tag of the RFID device to be protected. The tagof the RFID device can include an LC tuned circuit, for example, set to13.56 MHz for operations with RFID devices and RFID readers thatcommunicate using this frequency. The RFID signal capture device caninductively couple with the inductor-capacitor (LC) tuned circuit of thetag of the RFID device to disrupt the signal received by the RFIDdevice. Note, because of the coupling of the RFID signal capture devicewith the RFID tag of the RFID device to be protected, a 6.78 MHz signalat one-half (½) the power, a 26 MHz (second harmonic), or both may bepresent to further disrupt the normal operation of the tag. Thisconfiguration has been found through testing to allow the RFID signalcapture device to provide protection to an RFID device at all distancesfrom the RFID reader when placed, for example, within ½-inch (12 mm) orso of the tag of the RFID device.

Further, because the antenna/coil/transceiver portion of the RFID signalcapture device is not a tuned circuit, according to this configuration,advantageously, the RFID signal capture device affects only the tag whenin close proximity as it must couple with the tuned circuit of the tagto operably function. As such, when not coupled with a tag, the devicehas substantially no effect on either the RFID device (or devices/tags)to be protected or on the RFID reader. Testing of the RFID signalcapture device according to this configuration showed that the RFIDreader could still read RFID tags not coupled with the RFID signalcapture device even when the device was physically placed on the reader.That is, as noted above, the RFID signal capture device, according tothis configuration, is activated by the electrical field that isproduced at the RFID tag's coil/antenna, and not merely from theincoming signal from the RFID reader independent of the RFID device tobe protected.

The RFID signal capture device can advantageously include an internalphase capture that changes the impedance of the tag's tuned circuit,which causes a phase variance of the 13.56 MHz carrier for the RFID tagwhen in close proximity, thus, inhibiting the tag of the protected RFIDdevice from responding to the reader. Also advantageously, the RFIDsignal capture device can be configured to function without a permanentinternal power source, thus preventing the RFID signal capture devicefrom radiating a signal without the passive RFID tag or tuned circuit toallow power harvesting, so that the device can only be activated whenthe electrical field is present in the RFID tag and when the two devicesare in close proximity In other words, the RFID signal capture deviceceases to function when the field is removed—i.e., when the RFID signalcapture device and the RFID device to be protected are sufficientlyphysically separated, regardless of the position of the RFID reader.

Advantageously, by providing user separable RFID or other contactlesscircuitry signal capture devices and RFID or other contactless circuitrydevices, various embodiments of combinations, devices and methods of thepresent invention advantageously provide flexibility, portability, anduser controlled protection for a user's RFID or other contactlesscircuitry device.

Another example of an embodiment of a device to prevent unauthorizedRFID interrogation (e.g., an RFID signal capture device), for example,performs such actions by preventing data transfer between a nearby RFIDreader including an RFID reader inductor and an RFID tag including anRFID tag inductor/coil (“antenna”), for example, carried by a personalidentification or financial transaction medium, which together form anRFID device to be protected. The device can include a container, asignal capture circuit carried by the container, and an interrogationindicator carried by the container.

The container can be, for example, in the form of a plastic card similarto a standard credit/debit card, an ID device or passport, oralternatively in another form such as, for example, a wallet, purse,card carrier, or other medium to carry both the RFID device to beprotected and the RFID signal capture device. In the alternative form, apocket or card holder section in the wallet, purse, etc., canadvantageously have the RFID signal capture device embedded therein toprotect any RFID devices (credit, debit, phone cards, etc., or ID cards)when stowed away in the respective wallet, purse, etc.

The signal capture circuit of the RFID signal capture device can beconfigured to mutually inductively couple with the RFID tag whenpositioned in close proximity thereto and when the RFID reader isproducing an interrogation signal to thereby effectively prevent datatransfer between the RFID tag and the RFID reader. The signal capturecircuit can include a signal capture circuit antenna separate from theantenna of the tag of the RFID device to be protected, but neverthelesspositioned to receive an interrogation signal carrying a data signalfrom the RFID reader directed to the RFID device to be protected, andcan include a signal processing portion operably coupled thereto. Thesignal processing portion can include a timing synchronizer and anamplifier/transistor/amplifier module positioned to return a modifiedcarrier signal responsive to the interrogation signal to therebyeffectively prevent the data transfer between the RFID reader and theRFID tag.

The interrogation indicator of the RFID signal capture device can beconfigured to indicate to a user of the RFID device carrying the RFIDtag that the RFID reader is attempting to interrogate the RFID tag whenboth positioned in close proximity to the RFID tag and when the RFIDreader is producing the interrogation signal. The interrogator indicatorcan include an interrogation indicator antenna positioned to receive aninterrogation signal from the RFID reader, a power circuit or module toharvest power and/or extended storage of power, and an indicator circuitmodule or other form of circuit including an audible indicator and/or avisual indicator, configured to indicate to the user of the RFID tagthat the RFID reader is attempting to interrogate the RFID tag when RFIDsignal capture device is positioned in close proximity to the RFID tagand when the RFID reader is producing the interrogation signal.

Another example of an embodiment of a device to prevent unauthorizedRFID interrogation, for example, by preventing data transfer between anearby RFID reader and an RFID device to be protected provides an RFIDsignal capture device including a container, a signal capture circuitcarried by the container and configured to mutually inductively couplewith the RFID tag when positioned in close proximity thereto and whenthe RFID reader is producing an interrogation signal, and can include aninterrogation indicator carried by the container and configured toindicate to a user of the RFID tag when positioned in close proximitythereto and when the RFID reader is producing the interrogation signalthat the RFID reader is attempting to interrogate the RFID tag.

The interrogation indicator can include an antenna positioned to receivean interrogation signal from the RFID reader, a voltage rectifierpositioned to provide operational interrogator indicator circuit powerresponsive to the interrogation signal, and an indicator including anaudible indicator and/or a visual indicator configured to indicate tothe user of the RFID tag that the RFID reader is attempting tointerrogate the RFID tag when RFID signal capture device is positionedin close proximity to the RFID tag and when the RFID reader is producingthe interrogation signal.

The RFID signal capture device, according to this configuration, canadvantageously not only indicate the presence of an interrogationsignal, but can also substantially disrupt the signal provided by theRFID reader so that the RFID device to be protected cannot properlyidentify the timing signal provided by the reader, and even ifidentified, cannot properly extract the data provided by the RFID readersufficient to be able to respond to thereby effectively prevent datatransfer between the RFID tag and the RFID reader. Further, even ifobtaining sufficient data to respond, the RFID signal capture device canadvantageously substantially disrupt the signal provided by the RFIDdevice to be protected so that the RFID reader is unable to extractsufficient data provided by the RFID device to be protected to eitherobtain the protected information or to identify the user in order totrack the actions or movement of the user.

Another example of an embodiment of a device to prevent unauthorizedRFID interrogation, for example, by preventing data transfer between anearby RFID reader and an RFID device to be protected, includes acontainer and a signal capture circuit carried by the container andconfigured to mutually inductively couple with the RFID transponder whenpositioned in close proximity thereto and when the RFID reader isproducing an interrogation signal of sufficient strength to interrogatethe RFID transponder and to prevent data transfer between the RFIDtransponder and the RFID reader responsive to being positioned in closeproximity to the RFID transponder and responsive to the RFID readerproducing an interrogation signal of sufficient strength to interrogatethe RFID transponder.

Embodiments of methods of enhancing protection against unauthorizedinterrogation of an RFID or other contactless circuitry device, are alsoprovided. An example of an embodiment of a method can includepositioning a separate RFID signal capture device adjacent a separateRFID device to block RFID interrogation and selectively separating theseparate RFID device from the separate RFID signal capture device forauthorized interrogation of the separate RFID device. Another example ofan embodiment of a method of enhanced protection against unauthorizedinterrogation of a contactless circuiting device includes positioning aseparate contactless circuitry signal capture device in association witha container and adjacent a separate contactless circuitry device tothereby block unauthorized interrogation of the separate contactlesscircuitry device, and selectively separating the separate contactlesscircuitry device from being adjacent the separate contactless circuitryblock device for authorized interrogation of the separate contactlesscircuitry device.

Another example of an embodiment of a method can include inductivelycoupling an RFID signal capture device with the RFID tag (or multipletags) being protected and the RFID reader to thereby effectively preventdata transfer between the RFID tag and the nearby RFID reader when theRFID signal capture device is positioned by a user in close proximity tothe RFID tag and when the RFID reader is producing an interrogationsignal, and inductively coupling the RFID signal capture device with theRFID tag when positioned in close proximity to the RFID tag and when theRFID tag is producing a reply to an interrogation signal.

The method can also include indicating to the user of the RFID tag thatthe RFID reader is attempting to interrogate the RFID tag when the RFIDreader is producing the interrogation signal and when the RFID signalcapture device is in close proximity to the RFID tag, whereby suchindication is not provided when the RFID signal capture device is not inclose proximity to the RFID reader (i.e., when the indicator circuit isnot receiving a sufficient signal strength). The indicating can includeilluminating a visual indicator carried by the RFID signal capturedevice, and/or sounding an audible indicator carried by the RFID signalcapture device.

The method can also include the step of allowing data to transferbetween the RFID device and an RFID reader by selectively substantiallyseparating the RFID signal capture device from being adjacent the RFIDtag to allow authorized interrogation of the RFID tag. Accordingly, theRFID signal capture device can be configured to not interfere withoperation of the RFID reader when the RFID signal capture device is notpositioned in close proximity to an RFID tag.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of theinvention, as well as others which will become apparent, may beunderstood in more detail, a more particular description of theinvention briefly summarized above may be had by reference to theembodiments thereof which are illustrated in the appended drawings,which form a part of this specification. It is to be noted, however,that the drawings illustrate only various embodiments of the inventionand are therefore not to be considered limiting of the invention's scopeas it may include other effective embodiments as well.

FIG. 1 is a perspective view of a combination of a separate RFID deviceand a separate RFID signal capture device positioned in a containeraccording to an embodiment of the present invention;

FIG. 2 is a schematic environmental view of a separate RFID device beinginterrogated by an RFID interrogation device;

FIG. 3 is a schematic environment view of a combination of a separateRFID device and a separate RFID signal capture device configured to bepositioned in a container according to an embodiment of the presentinvention;

FIG. 4 is a schematic diagram of an RFID signal capture device accordingto an embodiment of the present invention;

FIG. 5 is a schematic diagram illustrating inductive coupling between anRFID reader and an RFID device;

FIG. 6 is a schematic diagram illustrating data transmission between anRFID reader and an RFID device;

FIG. 7 is a schematic diagram of a signal capture circuit of an RFIDsignal capture device according to an embodiment of the presentinvention;

FIG. 8 is a schematic diagram of a signal capture circuit of an RFIDsignal capture device according to an embodiment of the presentinvention;

FIG. 9 is a schematic diagram of a signal capture circuit of an RFIDsignal capture device according to an embodiment of the presentinvention;

FIG. 10 is a schematic diagram of a signal capture circuit of an RFIDsignal capture device according to an embodiment of the presentinvention;

FIG. 11A is a schematic diagram of a signal capture circuit of an RFIDsignal capture device according to an embodiment of the presentinvention;

FIG. 11B is a schematic diagram of a signal disruptor circuit of an RFIDsignal disruptor device according to an embodiment of the presentinvention;

FIG. 11C is a schematic diagram of a pair of signal disruptor circuitsof an RFID signal disruptor device according to an embodiment of thepresent invention;

FIG. 11D is a schematic block diagram of a signal disruptor circuit ofan RFID signal disruptor device according to an embodiment of thepresent invention;

FIG. 11E is a schematic diagram of a signal disruptor circuit of an RFIDsignal disruptor device according to an embodiment of the presentinvention;

FIGS. 11F-11I are schematic block diagrams of variations of the signaldisruptor circuit of an RFID signal disruptor device of FIG. 11Daccording to an embodiment of the present invention;

FIG. 11J is a schematic diagram of a signal disruptor circuit of an RFIDsignal disruptor device according to an embodiment of the presentinvention;

FIG. 12 is a schematic diagram of an RFID signal capture devicepositioned in close proximity to an RFID device to be protected beinginterrogated by an RFID reader according to an embodiment of the presentinvention;

FIG. 13 is a schematic diagram of an RFID signal capture deviceinductively coupling with an RFID device to be protected in response toan interrogation by an RFID reader according to an embodiment of thepresent invention;

FIG. 14 is a schematic diagram of an audible/vibratory form of aninterrogation indicator circuit of an RFID signal capture deviceaccording to an embodiment of the present invention;

FIG. 15 is a schematic diagram of a visual form of an interrogationindicator circuit of an RFID signal capture device according to anembodiment of the present invention;

FIG. 16 is an image of a spectrum produced by an RFID reader with noRFID tags or RFID signal capture devices present;

FIG. 17 is an image of a spectrum produced by an RFID reader with anRFID signal capture device positioned adjacent the RFID reader, with noRFID tags present according to an embodiment of the present invention;

FIG. 18 is an image of a spectrum under normal read operations betweenan RFID reader and an RFID tag showing both carrier and data signatures;

FIG. 19 is an image of a spectrum when an RFID signal capture device isplaced adjacent an RFID tag during an attempted interrogation by an RFIDreader according to embodiment of the present invention;

FIG. 20 is an image of a spectrum when an RFID signal capture device andtest instrument antenna is placed adjacent an RFID tag during anattempted interrogation by an RFID reader, resulting in a parasiticoscillation;

FIG. 21 is a schematic diagram of a carrier wave emanating from an RFIDreader during normal operations;

FIG. 22 is a schematic diagram of an example representation of thecarrier wave of FIG. 21 being phase and amplitude adjusted as a resultof positioning the RFID signal capture device in close proximity to theRFID tag according to an embodiment of the present invention;

FIG. 23 is a schematic diagram of a data signal emanating from an RFIDreader during normal operations;

FIG. 24 is a schematic diagram of an example representation of the datasignal of FIG. 23 being phase and amplitude adjusted as a result ofpositioning the RFID signal capture device in close proximity to theRFID tag according to an embodiment of the present invention;

FIG. 25 is a perspective view of an RFID device positioned in acontainer;

FIG. 26 is a perspective view of an RFID device positioned in acontainer, positioned in a pocket of a user, and being interrogated byan unauthorized interrogator with an RFID interrogation device;

FIG. 27 is a perspective view of a combination of a separate RFID deviceand a separate RFID signal capture device positioned in a containeraccording to an embodiment of the present invention;

FIG. 28 is an environmental view of the combination of a separate RFIDdevice and a separate RFID signal capture device positioned in acontainer as illustrated in FIG. 25, positioned in a pocket of anauthorized user, and being interrogated by an unauthorized interrogatorwith an RFID interrogation device according to an embodiment of thepresent invention;

FIG. 29 is an environmental view of an authorized user using a separateRFID device for an authorized RFID read after selective removal of thesame from a container having a combination of a separate RFID and aseparate RFID signal capture device positioned therein according to anembodiment of the present invention;

FIG. 30 is an environmental view of a separate RFID device beingreturned to a container so that the container has a combination of aseparate RFID device and a separate RFID signal capture device accordingto an embodiment of the present invention;

FIG. 31 is a schematic view of an RFID device positioned in a container;

FIG. 32 is a schematic view of a combination of separate RFID device anda separate RFID signal capture device positioned in the container shownin FIG. 31 according to an embodiment of the present invention;

FIG. 33 is a schematic block flow diagram of a method of preventing datatransfer between an RFID reader and an RFID tag according to anembodiment of the present invention; and

FIG. 34 is a schematic flow diagram of a method of preventing datatransfer between an RFID reader and an RFID tag according to anembodiment of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, which illustrate embodiments ofthe invention. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theillustrated embodiments set forth herein. Rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art.Like numbers refer to like elements throughout. Prime notation, if used,indicates similar elements in alternative embodiments. Note, as usedherein, the terms “nearby” and “in close proximity” generally meanapproximately within the interrogation response field of the referred toradiofrequency identification (RFID) device, interrogation responsefield of the referred to RFID signal capture device, and/orinterrogation range of the referred to RFID interrogator or otherreader.

As perhaps best shown in FIGS. 1-5, various embodiments of the presentinvention provide a RFID signal capture device 40 including, forexample, a signal capture circuit 43 carried by a container (e.g.,plastic card 41) configured to effectively prevent data transfer betweena nearby RFID interrogator/scanner or other form of RFID reader 50 (see,e.g., FIG. 26) as known and understood by those skilled in the art, andan RFID device 30 including an RFID transponder or other circuittypically referred to as an RFID tag 33 as known and understood by thoseskilled in the art, which is configured to inductively couple with anRFID reader circuit 53 of the RFID reader 50. The RFID signal capturedevice 40, for example, in a preferred configuration, can protect theinformation contained in the RFID tag 33 carried by various RFID devices30 including any standard ISO 14443 and ISO 15593 credit or personal IDcard, etc., from being read surreptitiously. Beneficially, the preferredconfiguration of the RFID signal capture device 40 requires that thedevice 40 be in close proximity to the RFID card(s) or other devices 30to be protected, as shown, for example, in FIG. 3, in order to performits protective function. That is, according to the preferredconfiguration, when the device 40 is not near an RFID card(s)/device(s)30 to be protected, i.e., not within the interrogation response field ore-field 37 (see, e.g., FIG. 2), it will be powered down and will notinterfere with the normal operation of the RFID reader 50.

As perhaps best shown in FIG. 5, in order to function properly,inductively coupled passive RFID systems as known and understood bythose skilled in the art, need good coupling and maximum energy transferfrom the RFID reader circuit 53 of the RFID reader 50 to RFID tag 33.For this reason, such systems generally use parallel inductor-capacitor(“LC”) circuits in the tag antenna 35 and series LC circuits in thereader antenna 55, as understood by those skilled in the art. Togenerate the maximum power field in the RFID device 30, the RFID readercircuit 53 of the RFID reader 50 is generally designed to achievemaximum coil/antenna current at the resonant frequency. Since currentthrough a coil generates a magnetic field, this field is generallymaximized in a series LC circuit, whose impedance approaches zero atresonance To maximize the voltage gain at resonance in an RFID tag 33, aparallel LC circuit is typically used which provides an impedance thatapproaches infinity at resonance. In a system designed to read standardISO 14443 and ISO 15593 cards 30, for example, the power provided by anappropriate RFID reader 50, or more particularly, the RFID readercircuit 53 of the RFID reader 50, generates at least a 3-volt field inthe RFID tag 33 when it is placed in proximity Note, hereinafter, theterms RFID reader circuit 53 and RFID reader 50 may be usedinterchangeably for illustrative purposes.

As perhaps best shown in FIG. 6, during normal operation of a financialor personal transaction between an RFID reader 50 and an RFID device 30,the RFID reader circuit 53 of the RFID reader 50 provides power, clock,and data for the tag 33 of the RFID device 30. The tag 33 will then“talk” back to the RFID reader 50 with the account number and otherinformation as understood by those skilled in the art. Most credit cardtransactions are very quick since the data transfer rate is quite high.

As perhaps best shown in FIGS. 7-8 and 12-13, and as will be describedin more detail later, the signal capture circuit 43 of the RFID signalcapture device 40 according to the illustrated configuration, has notuned circuit on the antenna, and therefore, must be coupled with theRFID device 30, for example, in order to be active. Once the RFID tag 33comes into contact with a signal from the RFID reader 50 (i.e., RFIDreader circuit 53) having a sufficient signal strength, the signalcapture circuit 43 of the RFID signal capture device 40 becomesinductively coupled with the RFID tag 33 of the RFID device 30 in atransformer-type circuit. Once sufficient operating power is achieved,the signal capture circuit 43 begins to disrupt communication betweenthe RFID device 30 and the RFID reader 50. According to the exemplaryconfiguration, this can be accomplished by capturing the e-field 37 ofthe tag 33 to thereby prevent the tag 33 from “seeing” the RFID reader'sdata. In this configuration, the signal capture circuit 43 uses energyfrom the field 37 of the tag 33 of the RFID device 30, and does not emitsignals back to the RFID reader 50 when not coupled with the tag 33 ofthe RFID device 30. Further, in this configuration, when a “nearby”multiple tags 33 and when each tag 33 is receiving a sufficient signalstrength from the RFID reader 50, the un-tuned signal capture circuit 43captures the e-field of at least one tag 33, but more preferably, eachof the tags 33, simultaneously, in order to protect all of the tags 33.

Inductively coupled systems, including passive 13.56-MHz RFID systemsused by the financial services industry, for example, generally behavelike loosely coupled transformers (see, e.g., FIG. 5) as understood bythose skilled in the art. The magnetic coupling between the primarywinding (e.g., reader antenna coil 55) and secondary winding (tagantenna coil 35) conveys power from RFID reader 50 to the RFID tag 33.Tuned LC circuits are typically used at these frequencies to maximizecoupling between the primary and secondary winding. The RFID reader 50continuously emits RF carrier signals and observes any received RFsignals for data.

Under normal unprotected operations, when within range of a passive RFIDtransponder, such as tag 33, for example, the presence of the tag 33modulates the RF field generated by the RFID reader circuit 53 of theRFID reader 50. The RFID reader circuit 53 correspondingly detects suchmodulation. Prior to modulating the RF field, the passively configuredtag 33 absorbs a small amount of energy emitted by the RFID readercircuit 53, which is used by the tag 33 to effectively transfer “send”the modulated data once sufficient energy is acquired from the RF fieldgenerated by the RFID reader circuit 53. The RFID reader circuit 53demodulates the signals modulated by the tag 33, and decodes theinformation for further processing. For RFID devices 30 expecting to beutilized in the presence of other RFID devices 30 and RFID devices 30carrying multiple RFID tags 33, the tags 33 may be configured with ananti-collision protocol, described later, which in a typical example,can cause each RFID tag 33 to slightly off-tune. Similarly, the RFIDreader circuit 53 may be configured with an anti-collision protocolwhich can cause the RFID reader 50 to slightly off-tune.

Under protected operations, i.e., when the signal capture circuit 43 ofthe RFID signal capture device 40 is positioned in close proximity tothe RFID tag 33, or vice versa, the e-field 37 required by the RFID tag33 is disrupted. When protecting multiple closely positioned RFID tags33, simultaneously, the inductive coupling of the RFID signal capturedevice 40 can be with only one of the RFID tags 33 to sufficientlydisrupt or suppress the e-field 37 of each RFID tag 33. Note, any sinewave signal will activate the RFID signal capture device 40 provided thepower level is strong enough, and the RFID signal capture device 40 isin close proximity to the RFID tag 33. As such, according to theexemplary configuration, protection can be provided to each of the RFIDtags 33, as long as the RFID tags 33 are within the e-field 47 of thesignal capture circuit 43 of the RFID signal capture device 40 whenbeing activated.

According to the configuration illustrated in FIGS. 12-13, atime-variant field from the RFID reader circuit 53, which readercoil/antenna 55 generates and the tag coil/antenna 35 receives, inducescurrent and voltage across the tag coil/antenna 35 as understood bythose skilled in the art. The signal capture circuit 43 of the RFIDsignal capture device 40 effectively captures this energy when coupledwith an RFID tag 33 and performs one or more disruptive functions whichresultingly prevent any useful data exchange. Such disruptive functionscan include frequency-based data modulation (e.g., frequency shiftkeying or analog frequency modulation), phase-based data modulation(e.g., phase shift keying or analog phase modulation), and/oramplitude-based data modulation (e.g., amplitude shiftkeying/backscatter modulation, on-off shift keying, tuning-detuning, orvarious forms of digital or analog amplitude modulation) as understoodby those skilled in the art.

Further, as perhaps best shown in FIGS. 14 and 15, and as will bedescribed in more detail later, the RFID signal capture device 40,according to the illustrated configuration, can include an interrogationindicator 63 configured to indicate to a user of the RFID device 30 thatan RFID interrogator or other reader 50 is attempting to interrogate theRFID tag 33, or more particularly, to indicate when the interrogationindicator 63 of the RFID signal capture device 40 is receiving a signalof sufficient strength to interrogate the RFID tag 33, regardless ofposition—i.e., when the RFID reader 50 is producing aninterrogation/read signal (i.e., power and/or handshake signal)sufficient to read data from the RFID tag 33 of the RFID device 30(i.e., sufficient when not being protected). This embodiment of theinterrogation indicator 63, can beneficially allow the user to sweep anarea or location with the RFID signal capture device 40 to determinewhether or not an RFID reader 50 signal is being generated, and/or toindicate that an RFID reader 50 is generating an interrogation signal ofsufficient strength when the RFID tag 33 is being protected against anunauthorized interrogation/read signal having a substantially sufficientstrength to read data from the RFID tag 33. In a first alternateconfiguration, the interrogation indicator 63 can identify aninterrogation signal having a signal strength substantially less thanthat required to read the protected RFID device 30, but greater thanthat of background noise. In a second alternate embodiment of theinterrogation indicator 63, the interrogation indicator 63 can beconfigured to indicate that an RFID reader 50 is generating aninterrogation signal of sufficient strength to read data from the RFIDdevice 30 only when the RFID tag 33 is positioned in close proximity tothe signal capture circuit 43 of the RFID signal capture device 40 andwhen the RFID reader circuit 53 of the RFID reader 50 is producing aninterrogation/read signal sufficient to read data from the RFID device30.

The interrogation indicator 63 can include an interrogation indicatorantenna 65 as understood by those skilled in the art, positioned toreceive an interrogation signal from the RFID reader circuit 53 of theRFID reader 50, and an indicator such as, for example, anaudible/vibration indicator 67 (e.g., piezoelectric, etc.) and/or avisual indicator 68 (e.g., LED, color sensitive film, etc.) asunderstood by those skilled in the art, configured to alert the user ofthe RFID device 30 of the presence of an interrogation signal (i.e.,that the RFID reader 50 is attempting to interrogate the RFID tag 33)when RFID signal capture device 40 is positioned in close proximity tothe RFID tag 33 and when the RFID reader 50 is producing theinterrogation signal. Regardless of the configuration, an indication ofattempted or actual data transfer can be provided in the form of achirping of the audible/vibration indicator 67 or a flicker of thevisual indicator 68. Similarly, an indication of an attempted or actualinterrogation without data transfer or an interrogation where the datasignal riding on the carrier signal is, for example, too high to bevisually or audibly distinguished from the carrier signal can beprovided, for example, in the form of a relatively constant tone or humprovided by the audible/vibration detector 67 or a relatively steady orcontinuous illumination of the visual indicator 68. One of ordinaryskill in the art should recognize that other audible/vibration andvisual indications are within the scope of the present invention.

According to a preferred configuration, the antenna or antennae 65 isindependent of the RFID signal capture device antenna (e.g., signalcapture circuit antenna/assembly 45), and the RFID device antenna 35.According to embodiments using physical circuit elements (e.g., wire,fiber optics, chemicals, or inks), the indicator 63 can also include avoltage rectifier 69 to increase the power harvesting capability of theindicator 63.

Note, although illustrated in the form of electricity conductingcircuits, the interrogation indicator 63 can alternatively take the formof a chemical combination or compound as known to the skilled in theart, positioned on a surface of the RFID signal capture device 40, whichwill illuminate (e.g., glow) when exposed to the carrier frequency ofthe RFID reader 50, to indicate the presence of an RFID interrogationsignal to the user.

Various tests were performed on an example of an embodiment of the RFIDsignal capture device 40 for the protection of a RFID device 30 in theform of various credit cards containing an RFID tag 33. Most of thepreliminary testing on standard ISO 14443 and ISO 15593 cards creditcards showed that the cards could be read from as much 6 to 8 inchesfrom the transmit antenna/coil 35 of the RFID reader 50. Hackers,however, have shown that these cards can be read from several feet awayusing illegal readers. Nevertheless, even FCC compliant readers can besmall, portable and wireless, and will fit into a handbag or other smallcase, to facilitate an unauthorized interrogation to acquire criticalcredit card or other personal information.

FIG. 16 illustrates a display of a spectral analyzer showing thespectrum at 71 of a 13.56 MHz RFID reader 50, with no RFID tags 33 orRFID signal capture devices 40 present, as “seen” by a tunedinstrumentation pickup test antenna (not shown) of a spectral analyzer(not shown) placed approximately 12 inches over the reader's antenna 55.The spectral analyzer was set with a center at −30 db with a −70 dbfull-scale to the noise, 5 MHZ per division, and with the test antennapositioned approximately 12 inches from the RFID reader 50. The noiseshown at 72 around bottom of the spectrum is ambient noise. There areoccasional sweeps of data as the RFID reader 50 polls for tags 33. Theleft most spectrum is the zero reference and the center most spectrum isthe 13.56 MHz carrier of the RFID reader 50 used in the test.

FIG. 17 illustrates the spectrum shown at 71′ of the RFID reader 50 witha RFID signal capture device 40 having a signal capture circuit 43according to the configuration shown in FIG. 7, placed 2 inches fromreader antenna 55, with no RFID tag 33 present. It can be seen from thedisplayed spectrum that the RFID signal capture device 40 did notactivate in absence of an RFID tag 33.

FIG. 18 illustrates the spectrum shown at 71″ of the RFID reader 50under a normal read operation with an RFID device 30 to be protected inthe form of an American Express® Blue Card containing an RFID tag 33placed on the RFID reader 50 with the instrumentation pickup antenna(not shown) positioned adjacent to the RFID reader antenna 55. The datashown at 73 is at the base of the center-most spectrum 73 (13.56 MHzbirdie).

FIG. 19 illustrates the spectrum shown at 71′″ when the RFID signalcapture device 40 is placed on the RFID test device 30 including RFIDtag 33. It can be seen that no successful data transfer is present whenthe RFID signal capture device 40 is next to the RFID device 30 undertest (American Express® Blue Card).

FIG. 20 illustrates the spectrum shown at 71″″ when the RFID signalcapture device 40 and the RFID device 30 under test (containing an RFIDtag 33) are placed together with the RFID reader antenna 55 andinstrumentation pickup antenna (tuned sampling antenna). The result isparasitic oscillation shown at 74, which are no longer present when thedevices 30, 40, are moved approximate 2 inches away from the RFID reader50, so that the RFID signal capture device 40 cannot couple with theRFID reader antenna 55. Note, the parasitic oscillation may further bethe result of the instrumentation pickup antenna being in closeproximity to the RFID signal capture device 40.

In summary, it was shown by the testing that the signals created by theRFID signal capture device 40 are parasitic to the RFID tag 33 of theRFID device 30 under test, at least partially as a result of capturingthe data signal between the RFID tag 33 and the RFID reader 50 in orderto phase cancel the carrier. During the test, the data signalsconsistently registered at −30 db below the normal signal level of the13.56 MHz carrier, with a bandwidth of about 1 MHz. The data shown onthe display of the spectrum analyzer is from the powered RFID reader 50and not the RFID tag 33 of the device 30 under test. The signal levelsof the RFID tag 33 and the RFID signal capture device 40 (both passive)are so low that they could not be seen without placing theinstrumentation pickup antenna directly on top of the devices 30, 40.The addition of a tuned coil antenna into the coupled field caused thesignal displayed on the spectrum analyzer to oscillate (over-sample).

As identified previously, the RFID signal capture circuit 43 for theRFID signal capture device 40 is specifically designed to effectivelyprevent data transfer between an RFID tag (transponder) 33 of an RFIDdevice 30 and a RFID reader 50 attempting an unauthorized interrogationof data from the tag 33, when positioned in close contact with the RFIDdevice 30, to thereby perform various privacy functions including theprevention of unauthorized data access and/or the prevention of trackingthe movement of the user of the RFID device 30, while allowing accesswhen not positioned in close contact. To accomplish such functions, thecircuit 43 is generally configured: to mutually inductively couple withthe RFID tag (or tags) 33 when positioned in close proximity thereto andwhen the RFID reader 50 is producing an interrogation signal; tomutually inductively couple with the RFID reader 50 when positioned inclose proximity to the RFID tag 33 (or at least one of the tags 33, buttypically all of the tags 33, if simultaneously protecting multiple tags33) when the RFID reader 50 is producing an interrogation signal; tomutually inductively couple with the RFID tag or tags 33 when positionedin close proximity to the RFID tag or tags 33 and when the respectiveRFID tag or tags 33 are producing a reply to interrogation signal in thepresence of the RFID reader 50; and to remain inert when not positionedin close proximity to the RFID device (or devices) 30 carrying the RFIDtag or tags 33 to not interfere with operation of the RFID reader 50 orthe RFID tag or tags 33, i.e., in order to allow the RFID reader 50 toconduct a transaction with the RFID device 30 or a selected one of theRFID devices 30. In order to remain inert when not positioned in closeproximity to the RFID device (or devices) 30, beneficially, the device40 can be configured to have no tuned circuit on the antenna/assembly45, resulting in a requirement for the device 40 to be inductivelycoupled with an RFID tag 33 of an RFID device 30 in order to beactivated.

FIG. 7 illustrates an example of an embodiment of the RFID signalcapture circuit 43 carried by the body 41 of the RFID signal capturedevice 40 (which can function as a container for the circuit 43). Theillustrated RFID signal capture circuit 43 includes a signal capturecircuit antenna/assembly 45 as understood by those skilled in the art,positioned to receive an interrogation signal including an interrogationcarrier signal carrying a data signal from the RFID reader 50, and asignal processing portion 49 operably coupled thereto. When configuredin the form of a passive or partially passive circuit, the signalprocessing portion 49 of the signal capture circuit 43 can include avoltage rectifier power/data separator, e.g., voltage rectifier 91, asunderstood by those skilled in the art, positioned to provideoperational power to the remainder of the signal processing portion 49responsive to the interrogation signal. In this configuration, thevoltage rectifier 91 is normally in the form of a full wave rectifier toprovide the maximum amount of power in the minimum amount of RFID readersignal transmission time. Further, according to a preferredconfiguration, the circuit 43 does not include a battery or otherlong-term storage device to power the signal capture circuit 43, andthus, will not transmit without receiving energy from an interrogationsignal when coupled with the RFID tag 33.

The signal processing portion 49 of the signal capture circuit 43 canfurther include a timing synchronizer 93 as would be understood by thoseskilled in the art, positioned to return a modified carrier signalresponsive to the interrogation signal. The modified carrier signal caninclude a phase-adjusted carrier signal generated in response to theinterrogation signal, and/or a synchronized carrier signal generated inresponse to the interrogation signal, for transmission as either asynchronized signal or phase adjusted signal, for example, by atransistor or amplifier 95 as would be understood by those skilled inthe art, coupled with the antenna/assembly 45. When provided as aphase-shifted carrier signal, the phase-shifted carrier signal returnedby the timing synchronizer 93 can have a phase shift of at leastapproximately 90 degrees to that of the interrogation carrier signal,but preferably has a phase shift of approximately 180 degrees, toeffectively cancel or at least severely disrupt any attempt by the RFIDreader 50 to transfer data to the RFID tag 33.

The signal capture circuit 43 can further include a time/data separator97 as would be understood by those skilled in the art, positioned toseparate the data signal from the interrogation signal to provide thetiming synchronizer 93 a timing reference to the interrogation carriersignal to facilitate the phase adjustment and/or synchronization, and adata detector 99 as would be understood by those skilled in the art,positioned to provide the data signal to the timing synchronizer 93 andpositioned to facilitate data modulation of the phase-adjusted carriersignal and/or data modulation of the synchronized carrier signal.Beneficially, the data modulated signal can have a different data signalthan the data signal received from the RFID reader 50 to thereby furthereffectively prevent data transfer between the RFID tag 33 and the RFIDreader 50. Note, it should be understood by one skilled in the art thatalthough shown as separate functional components, various methodologiesof implementing voltage rectifier 91, timing synchronizer 93, transistoror amplifier 95, time/data separator 97, and data detector 99, toinclude implementation as either separate modules or a single module, iswithin the scope of the illustrated embodiment of the present invention.

As noted previously, beneficially, the data modulation can includefrequency-based data modulation, phase-based data modulation,amplitude-based data modulation, and others known to those skilled inthe art, provided to prevent/disrupt the RFID tag 33 from being able toreceive or understand a transmission from the RFID reader 50 via theRFID reader circuit 53, and to prevent/disrupt the RFID reader 50 frombeing able to receive or understand a transmission from the RFID tag 33if the transmission from the RFID reader circuit 53 was received by theRFID tag 33. Various methods of providing preventive or disruptive phasemodulation of the carrier frequency were described above. Preventive ordisruptive frequency modulation can be provided by modulating asynchronized carrier frequency to provide different data, such as, forexample, random data, or data specifically at odds with the datadetected by data detector 99. According to an embodiment of the signalcapture circuit 43, both phase and frequency modulation can besimultaneously provided. Note, although the terminology phase modulationand frequency modulation are used, one skilled in the art shouldunderstand that such terminology refers to both analog modulation in itsvarious forms, and digital modulation (e.g., phase shift keying,frequency shift keying) in its various forms.

Similarly, preventive or disruptive amplitude modulation in its variousforms can be provided by either randomly adjusting the amplitude oradjusting the amplitude based on the data recognized, for example, bythe data detector 99. The carrier produced by the RFID reader circuit 53of the RFID reader 50 produces an AC voltage that is generated by the LCcircuit combination of the RFID tag 33 and in the signal capture circuit43 when inductively coupled with the RFID tag 33 via the signal capturecircuit antenna/assembly 45. This voltage is rectified by the voltagerectifier 91 to provide DC voltage to power the rest of the signalcapture circuit 43. Note, the analog modulation can be simultaneouslyprovided with phase modulation, frequency modulation, or both.

In amplitude shift keying, for example, a transistor oramplifier/amplifier module 95 manipulates the amplitude of the signal tocreate a logical “one” or “zero.” One methodology of amplitude shiftkeying can include application of a circuit 43′ having a tapped antennacoil/assembly 45′ as shown, for example, in FIG. 8, connected to amodulation transistor or amplifier 95 so that when the circuit is “on,”it effectively lowers the inductance of the antenna coil/assembly 45′.According to this exemplary methodology, when the signal capture circuit43′ is “off,” the RFID tag 33 “sees” an inductance and capacitance inparallel tuned to 13.56 MHz in this example. As the data is sent to theRFID tag 33 by the RFID reader circuit 53 of the RFID reader 50,however, the signal capture circuit 43′ turns “on” and “off” to producefalse data. That is, in this example, when a signal from the RFID readercircuit 53 is applied to the signal capture circuit 43′ and the circuit43′ is positioned in close proximity to the RFID tag 33, the LC circuitis tuned and detuned continuously at a rate equal to the frequency ofthe controlling signal. This control signal is used to alter the datadetected in the RFID reader circuit 53 as the amplitude-modulated formof the carrier. If of sufficient strength to be detected by the RFID tag33, the data detector used by the RFID tag 33 demodulates this falsesignal to try to extract information being sent from the RFID reader 50,which results in a communication failure between the RFID reader 50 andthe RFID device 30.

Another protection methodology that can be employed in conjunction withor as an alternative to the above described modulation forms includesusing the carrier frequency of the RFID reader 50 to generate a harmonicfrequency, e.g., 6.78 MHz and/or 27.12 MHz for a 13.56 MHz carrier, thatis, for example, approximately 70 percent or more in field strength tothat of the carrier frequency as seen by the RFID tag 33. This harmoniccan be radiated so that the data and timing present on the carrierfrequency of the RFID reader 50 are disrupted to the extent that theRFID reader/interrogator 50 is unable to communicate with the protectedRFID device 30. That is, since the RFID tag 33 of the RFID device 30cannot receive the data transmissions, it cannot communicate.

FIGS. 21-24 comparatively illustrate the functioning of the signalcapture circuit 43 shown, for example, in FIG. 7. FIG. 21, for example,illustrates a generic example representation of a carrier wave shown at81 as seen by an RFID tag, e.g., RFID tag 33, which would emanate fromthe RFID reader 50, and FIG. 23 illustrates an example of the power,timing, and data signals from the RFID reader 50 shown at 82, 83, and84, respectively. Specifically, FIG. 23 illustrates that an initialportion of the signal from the RFID reader 50 (power portion at 82)would be utilized by a passive RFID tag, e.g. RFID tag 33, to obtainpower to begin functioning, followed by a timing portion of the signalat 83, further followed by a validated data portion of the signal at 84,which the RFID tag 33 would need to receive in order to respond to theinterrogation.

FIG. 22 comparatively illustrates an example representation shown at 81′of the carrier wave 81 of FIG. 21 being phase and amplitude adjusted asa result of positioning the RFID signal capture device 40 in closeproximity to the RFID tag 33, and FIG. 24 comparatively illustrates theinsertion of random data shown at 84′ beginning during transmission ofthe “power” signal shown at 82′ which affects both the timing and thedata signals, thus preventing tag 33 recognizing any data provided bythe RFID reader 50 when the RFID signal capture device 40 in closeproximity to the RFID tag 33.

FIG. 9 illustrates another example of an embodiment of the RFID signalcapture circuit 43″ that can be carried by the body 41 of the RFIDsignal capture device 40. The illustrated RFID signal capture circuit43″ can include one or more receiver antennas 101, 103, as understood bythose skilled in the art, to assist in receiving RFID interrogationsignals, a receiver and demodulator 105, 107 to demodulate a receivedinterrogation signal, a power generator module 109, 111, as would beunderstood by those skilled in the art, to generate power for the RFIDsignal capture circuit 43″ responsive to the received interrogationsignal, and a signal mixer and frequency generation module (analog ordigital) 113, as would be understood by those skilled in the art, to mixreceived signals and generate a frequency signal as understood by thoseskilled in the art. The circuit 43″ can also include, for example, atransmitter power level controller 115, 117 and one or more transmitterantennas 119, 121 to assist with the transmission of the blocking RFfields or zones, as would be understood by those skilled in the art.

An embodiment similar to that of the RFID signal capture circuit 43″described above, can functionally include an incoming signal detector todetect incoming signals from the unauthorized RFID interrogation deviceor other form of RFID reader 50, an incoming signal demodulator todemodulate a detected incoming signal, and an RFID signal disruptor ordisruptor circuit configured to respond to the RFID reader 50 withdisrupting read signals responsive to the incoming signal, as would beunderstood by those skilled in the art. The RFID signal disruptorcircuit can include various configurations, one of which includes anRFID signal generator as would be understood by those skilled in theart, to generate an RFID signal at the same data rate as the demodulatedsignal to thereby disrupt the RFID device's ability to communicate withthe unauthorized interrogation device or reader 50.

Another similar embodiment of an RFID signal capture device 43″ canfunctionally include an incoming signal detector to detect incomingsignals from the unauthorized RFID interrogation device or reader 50 andan RFID interferer configured to interfere with activation or operationability of the RFID tag 33 of each separate RFID device (or devices) 30as would be understood by those skilled in the art, responsive to theincoming signal detector so that the RFID reader 50 cannot properly reador have access to information on the RFID device or devices 30. The RFIDinterferer can also interfere with the RFID device (or devices) 30(including those having an anti-collision protocol) so that theanti-collision protocol fails to activate.

Alternatively, for example, for an RFID device (or devices) 30 includingan anti-collision protocol as understood by those skilled in the art,the RFID interferer interferes with a product of the anti-collisionprotocol of the separate RFID device (or devices) 30 when beingtransmitted to the unauthorized RFID reader 50. The RFID interferer, forexample, can include a frequency shift generator as would be understoodby those skilled in the art, to generate a frequency shift above andbelow a center frequency of an RFID communication link to each separateRFID device 30.

FIGS. 10-11A illustrate two examples of more detailed antenna arrays (orinductors), capacitors, diodes, and amplifiers arranged as understood bythose skilled in the art to prevent data transfer between the RFIDreader 50 and the RFID device 30. For example, as understood by thoseskilled in the art, the signal capture circuit 43, 43′, 43″, can be inthe form of an application specific integrated circuit (ASIC) 131 usedto interface and respond to an antenna array in a low power design suchas shown in FIG. 10. The low power ASIC 131 can have digital sampling todetect incoming signals from the RFID reader 50 or other interrogationdevice, and can use various signal generation or frequency generationtechniques as understood by those skilled in the art to respond withdisruptive patterns.

As understood by those skilled in the art, and as noted above, RFID tags33 or other circuitry or chips carried by the RFID device 30 often havean anti-collision protocol or program that allow multiple chips to talkto a reader 50. Similarly, the RFID reader circuit 53 may be configuredwith an anti-collision protocol which can cause the RFID reader 50 toslightly off-tune to acquire the signal from an off-tuned RFID tag 33.Beneficially, the above described techniques can generate aninterference with the ability of each RFID tag 33 to activate itsonboard anti-collision protocol(s). Depending on the desires of the userof the RFID signal capture device 40: the anti-collision protocol(s) canbe stopped before activation; the product or result of the protocol canbe attacked or interfaced with during generation or transmission; orboth. A frequency, phase, or amplitude shift generation, for example,above and/or below a center frequency of an RFID communication link, canbe produced by the signal capture circuit to perform search functions.

Alternatively, an analog or discrete design, such as that shown in FIG.11A, can demodulate the incoming signal from the interrogationdevice(s), then broadcast back out at that data rate to suppress theability of the RFID tag 33 of each RFID device 30 to communicate.

As understood by those skilled in the art, the signal capture circuit43, 43′, 43″, could be in the form of individual component die, or thecommercially available component packages (SOT-23, SMB, etc.), used tointerface and respond to an antenna array as shown in FIGS. 11A-11H.Additionally, these analog based interference techniques could bepackaged as a single Analog ASIC package for ease of mass productionmanufacturing techniques.

FIGS. 11A-11J illustrate examples of a signal disruptor circuit whichcan be stored in a container such as, for example, a plastic card 41,wallet/purse 141, passport card, etc.

FIG. 11B illustrates a signal disruptor circuit 151 which includes afirst antenna 152 primarily for receiving an interrogation signal, asecond antenna 153 primarily for transmitting a disruptive signal,transistors 154, 155 (e.g., PNP bipolar junction transistors), and adiode 156 in parallel with a capacitor 157 jointly connected between theemitters of the transistors 154, 155 and a tap in the second antenna153.

FIG. 11C illustrates an example of a pair of signal disruptor circuits161, 161′, configured to produce signals that are 180° out of phase tobe used independently or by a signal mixer (not shown) to enhancedisruption of an unauthorized RFID interrogation. Each circuit caninclude an antenna 162 for receiving portions of the unauthorized RFIDinterrogation signal, a capacitor 163 positioned in parallel with theantenna 162, a transistor 164, 164′, to provide high-speed switchingwith minimal propagation delay between the incoming interrogation signaland the outgoing disrupting signal, and a resistor 165 in parallel witha diode 166 to stabilize the base voltage of the transistor 164, 164′.Each circuit can also include an inductor 167 provided to regulatecurrent to feed the transistor 164, 164′, as it switches the disruptivesignal onto the antenna.

FIG. 11D and FIGS. 11F-11H and 11I illustrate block diagrams of a set ofsignal disruptor circuit examples. FIG. 11E illustrates a practicalsignal disruptor circuit 171′ example of the RFID signal disruptorcircuit 171 (FIG. 11D). As shown in FIG. 11D, a signal disruptor circuit171 includes a transducer 172, a high-speed switch 173, a voltageregulator 174, a signal ringer/inductor 175, and a frequency regulator176.

The transducer 172 can include, for example, an RFID antenna 191 (see,e.g., FIG. 11E) typically positioned in a single plane or pair ofplanes.

The high-speed switch 173 can include, for example, a single transistor192 (see, e.g., FIG. 11E) or relatively small set of transistors toprovide high switching speeds, sufficient to minimize the propagationdelay between the received unauthorized RFID interrogation signal andthe disrupting signal such that the disrupting signal remains effectivein preventing the communication of usable data from one or more adjacentRFID devices 33 to be protected. According to an exemplary embodiment,the high-speed switch 173 has a responsiveness of typically less thanbetween approximately 10 μs and 0.1 μs, but more typically approximately1 μs. According to an embodiment, the transistor 192 according to anexemplary configuration is rated to consistently switch signals in theoperational frequency of 200 Mhz over a broad voltage range. Accordingto another exemplary configuration, a 7400 series gate is rated toswitch in the operational frequency range of 40 Mhz at low voltages and100 Mhz at higher voltages. The voltage being generated in the RFIDsignal disruptor circuit 171, 171′ can vary significantly while thedisruptor device is powering up for operation within the RFID field.

The voltage regulator 174 can include, for example, resistor 193 (see,e.g., FIG. 11E) positioned to stabilize base voltage of the transistor192 to thereby consistently drive the transistor 192 or other switchover a range of voltages associated with the received RFID interrogationsignal. A resistor is designed to resist a change in voltage in thecircuit. According to an exemplary configuration, the resistor 193 isemployed to stabilize the base voltage of the transistor 192 in order toconsistently drive the transistor even as the field generated voltagesvary.

The signal ringer 175 can include or consist of, for example, a woundinductor 194 (see, e.g., FIG. 11E) positioned in the circuit to causesignal ringing as understood by one of ordinary skill in the art inresponse to the received portions of the RFID interrogation signal. Awound inductor 194 is designed to resist a change in current in acircuit. According to an exemplary configuration, the inductor 194 actsas a current regulator to feed the transistor 192 as it switches thedisruptive signal onto the antenna 191. The inductor will generally notsubstantially regulate the voltage across the transistor 192, thereforevoltage spikes are regularly generated which provide a “ringing” effectof an oscillation. To assist in the isolation, the signal ringer 174 canalso incorporate capacitor 195 and/or parasitic capacitance included inthe other circuit components.

The frequency regulator 176 can include or consist of, for example, adiode 196 such as, for example, a varactor (varicap) diode (see, e.g.,FIG. 11E) to help control the frequency characteristics of thedisruptive signal. Particularly, in an exemplary configuration, thediode 196 assists in tuning the signal disruptor circuit 171, 171′, fordifferent frequencies and allows for protection directed to multipleinterrogation frequencies with the same signal disruptor device.

FIGS. 11F-11H illustrate variations of the RFID signal disruptor circuit171 according to various configurations.

FIG. 11J illustrates a practical RFID signal disruptor circuit 271′example of the RFID signal disruptor circuit 271 (FIG. 11I). As shown inFIG. 11I, a signal disruptor circuit 271 includes a transducer 272, ahigh-speed switch 273, a voltage regulator 274, a signal ringer/inductor275, and a voltage rectifier and visual operation indicator 276.

The transducer 272 can include, for example, an RFID antenna 291 (see,e.g., FIG. 11J) typically positioned in a single plane or pair ofplanes.

The high-speed switch 273 can include, for example, a single transistor292 (see, e.g., FIG. 11J) or relatively small set of transistors toprovide high switching speeds, sufficient to minimize the propagationdelay between the received unauthorized RFID interrogation signal andthe disrupting signal such that the disrupting signal remains effectivein preventing the communication of usable data from one or more adjacentRFID devices 33 to be protected. According to an exemplary embodiment,the high-speed switch 273 has a responsiveness of typically less thanbetween approximately 10 μs and 0.1 μs, but more typically approximately1 μs. According to an embodiment, the transistor 292 according to anexemplary configuration is rated to consistently switch signals in theoperational frequency of 200 Mhz over a broad voltage range. Accordingto another exemplary configuration, a 7400 series gate is rated toswitch in the operational frequency range of 40 Mhz at low voltages and100 Mhz at higher voltages. The voltage being generated in the RFIDsignal disruptor circuit 271, 271′ can vary significantly while thedisruptor device is powering up for operation within the RFID field.

The voltage regulator 274 can include, for example, resistor 293 (see,e.g., FIG. 11J) positioned to stabilize base voltage of the transistor292 to thereby consistently drive the transistor 292 or other switchover a range of voltages associated with the received RFID interrogationsignal. A resistor is designed to resist a change in voltage in thecircuit. According to an exemplary configuration, the resistor 293 isemployed to stabilize the base voltage of the transistor 292 in order toconsistently drive the transistor even as the field generated voltagesvary.

The signal ringer 275 can include or consist of, for example, a woundinductor 294 (see, e.g., FIG. 11J) positioned in the circuit to causesignal ringing as understood by one of ordinary skill in the art inresponse to the received portions of the RFID interrogation signal. Awound inductor 294 is designed to resist a change in current in acircuit. According to an exemplary configuration, the inductor 294 actsas a current regulator to feed the transistor 292 as it switches thedisruptive signal onto the antenna 291. The inductor will generally notsubstantially regulate the voltage across the transistor 292, thereforevoltage spikes are regularly generated which provide a “ringing” effectof an oscillation. To assist in the isolation, the signal ringer 274 canalso incorporate capacitor 295 and/or parasitic capacitance included inthe other circuit components.

The voltage rectifier and visual operation indicator 276 can include orconsist of, for example, a diode such as, for example, a light emittingdiode 296 (see, e.g., FIG. 11J) or other visual indicator as understoodby those skilled in the art. The voltage rectifier and visual operationindicator 276 can be positioned within the circuit to help maintain a DCvoltage in the circuit, for example, via voltage rectification,resetting after each phase shift. Additionally, the voltage rectifierand visual operation indicator 276 can also or alternatively provide avisual indication (alert) to the user of the RFID device 30 of thepresence of an interrogation signal; i.e., an indication that the RFIDreader 50 is attempting to interrogate the RFID tag 33 when the RFIDsignal disruptor circuit 271, 271′ is positioned in close proximity tothe RFID tag 33, sufficient to allow mutual inductive couplingtherebetween, when the RFID reader 50, 50′ is producing an interrogationsignal within activation range of the RFID tag 33. Beneficially, thevoltage rectifier and visual operation indicator 276 when included inthe RFID signal disruptor circuit 271, 271′ can perform the function ofvisual warning circuit 63 (FIG. 15), described previously, but in asingle RFID signal disruptor circuit arrangement.

As understood by those skilled in the art, these are only a feweffective examples according to embodiments of systems, combinations,devices and methods of the present invention, other examples andtechniques according to an embodiment of the present invention will beapparent to those skilled in the art. For example, the respectivetransistors 154, 155, 164, 164′, 192, where each shown as bipolarjunction-type transistors. Various types of field effect transistors orother types of switching/amplification units as understood by those ofordinary skill in the art can be employed in their place. For each ofthe above examples, in preferred configurations, the signal disruptorcircuits are not tuned with the RFID interrogator circuit, and thus,rely on mutual inductive coupling with one or more adjacent RFID devices32 thereby affect signal disruption.

FIGS. 25-26 illustrate an RFID device 30 in the form of a credit/debitcard carrying the RFID tag 33 and positioned in a separate container(illustrated in the form of a wallet). As can be seen from theillustrations, when an unauthorized RFID interrogation occurs, i.e.,when a scanning device (“interrogation device”) or other form reader 50is positioned within the interrogation response field or e-field 37 ofthe RFID tag and attempts to read the separate RFID device 30 fromwithin the container 141, the data (e.g., credit/debit card accountnumber, account ID, PIN, or any other data stored on the tag 33) can bereadily extracted.

In contrast, FIGS. 27-30, along with FIGS. 1-3, illustrate an example ofan embodiment of a combination of the separate RFID device 30 containinga RFID tag 33 and a separate RFID signal capture device 40 containing asignal capture circuit 43, each configured to be positioned separatelyinto, or to be associated with, both the body 41 of the RFID signalcapture device 40 functioning as a container 41 carrying the circuit 43,and/or a separate container 141. Accordingly, the combination includes aseparate RFID device and/or devices 30 configured to be positioned inthe container 141 with a separate RFID signal capture device 40,illustrated in the form of a plastic card similar to a credit card,configured to be positioned adjacent the separate RFID device and/ordevices 30 and in the container 141. That is, in the example shown inFIG. 27, the single RFID signal capture device 40 placed in a walletpocket provides protection to multiple RFID devices 30, simultaneously.Note, in an alternative embodiment of the present invention, the signalcapture circuit 43 can be directly embedded within or otherwise carriedby the container 141 adjacent to the card carrying portion (e.g.,wallet/purse credit card slot, etc.) to allow automatic protectionmerely by placing the RFID device and/or devices 30 (e.g., creditcard(s)) in the appropriate credit card slot, etc., of the container141.

In operation, when an unauthorized RFID interrogation occurs, i.e., whena scanning device (“interrogation device”) or other form reader 50attempts to read the separate protected RFID device/devices 30 fromwithin the container 141 (see, e.g., FIG. 28), the separate RFID signalcapture device 40 positioned adjacent the separate RFID device/devices30 prevents the attempted interrogation or read. When an authorized userU desires to use one of the separate RFID device 30 for an authorizedread, such as an authorized interrogation device 50, the authorized userU can selectively remove either the desired separate RFID device 30 orthe separate RFID signal capture device 40 and present the separate RFIDdevice 30 (within or outside of the container as long as sufficientlyseparated) for the authorized read by an authorized reader 50′ (see,e.g., FIG. 29). Note, when the RFID signal capture device 40 isprotecting multiple RFID devices 30, a preferred, if not required,procedure would be to remove the desired RFID device 30 to allow anauthorized read by an authorized reader (e.g., reader 50′ in FIG. 29),while maintaining protection of the remaining RFID devices 30 located,for example, in the container 141.

Note, the container 141 to carry the RFID signal capture device 40, forexample, can be in the form of a wallet, a passport, a purse, a folder,a pocket, an envelope, a card holder, a sleeve, and/or a display mount,just to name a few. According to embodiments where the signal capturecircuit 43 is directly carried by the container 141, rather thanindirectly via a separate container such as, for example, theillustrated body 41 of a plastic card (see, e.g., FIG. 1), the portionof the container 141 carrying the circuit 43 functionally becomes theRFID signal capture device 40 referred to herein. According to suchembodiments, the container 141 can also include other items therein,such as other credit or debit cards, money, jewelry, paper or sheets asunderstood by those skilled in the art. Note also, the container 141 isillustrated in FIGS. 25-30 as a separate holder for credit or debitcards, disembodied from the “plastic card” embodiment shown in FIG. 1and in FIGS. 25-30. As understood by those skilled in the art, however,numerous other types of containers or configurations are within thescope of the present invention to include a passport and clip or tag fora page in a passport (see, e.g., FIG. 32), and a readily removable clipor tag for a credit or debit card (not shown), just to name a few.

As noted above, an RFID device 30, for example, can be a credit card, adebit card, other transaction card (e.g. telephone, gift, electronic,smart) a passport, a passport cover or page, a drivers license, or otherdevice containing an RFID tag 33 as understood by those skilled in theart. FIGS. 1-3 and 25-30 illustrate credit or debit cards as RFIDdevices 30, and FIGS. 31-32 illustrate passports as RFID devices 30′.These are only for illustrative purposes and many other types of deviceshaving RFID tags 33 associated therewith can be used as well accordingto an embodiment of the present invention. Similarly, as noted above, anembodiment of a separate RFID signal capture device 40, for example,likewise can be a credit or debit card or other transaction card, tag,clip, sheet, or other device that also has circuitry or a chip 43.

As perhaps best shown in FIGS. 2-3 and 28, an RFID interrogation deviceor other form of reader 50 can be positioned separate and spaced-apartfrom an RFID device 30 a selected distance X and an interrogationresponse field or e-field 37 from the RFID tag 33 of the RFID device 30can be generated by the RFID device 30 in response to the interrogation.Concurrently, for example, a second e-field 47 can also be generated bythe RFID signal capture device 40 in response to the same interrogationto thereby generate a blocking zone 59 such as by disrupting theinterrogation signals, interfering with the transmitting signal from theRFID device 30, or other techniques understood by those skilled in theart, including those detailed previously.

Likewise, as shown in FIGS. 31-32, an RFID device 30′ such as in theform of a passport or passport cover can have RFID or other contactlesscircuitry or chip 33 associated therewith and can generate the RFe-field 37 responsive to the interrogation. An RFID or other contactlesscircuitry signal capture device 40′, such as in the form of a tag, clip,or page marker also having the RFID or other contactless blockingcircuitry (e.g., signal capture circuit 43, 43′, 43″), can be attachedto the passport 30′, such as one of the pages thereof, to generate an RFblocking field 75 or blocking zone 59, such as described previously.

As illustrated in FIGS. 1-34, embodiments of the present invention alsoinclude methods of preventing data transfer between a nearby RFIDinterrogation device or other reader 50 and an RFID transponder or tag33 to thereby enhance protection against unauthorized access to RFID orother contactless chip devices, and/or to prevent unauthorized trackingof the user based on the data stored in the tag 33. For example, anembodiment of such a method can include positioning a separate RFIDsignal capture device 40 adjacent one or more separate RFID devices 30to block or otherwise prevent RFID interrogation and selectivelyseparating a selected RFID device 30 from the separate RFID signalcapture device 40 for authorized interrogation of the selected RFIDdevice 30. The positioning, for example, can include either the separateRFID signal capture device 40 or the separate one or more RFID devices30 being in a container 141 prior to positioning the separate RFIDsignal capture device 40, adjacent the separate one or more RFID devices30. The prevented or otherwise disrupted RFID interrogation can includean unauthorized RFID interrogation. The container 141, for example, caninclude a wallet, a passport, a purse, a folder, a pocket, an envelope,a sleeve, a card holder, and a display mount. The blocking/prevention ofthe RFID interrogation, for example, can interfere with the activationof an anti-collision protocol associated with each separate RFID device30 or interfere with the transmission of an anti-collision protocolassociated with each separate RFID device 30, for example Alternatively,the blocking/prevention of the RFID interrogation can include providingdisrupting read signals responsive to an attempted interrogation of theseparate one or more RFID devices 30. Note, one of ordinary skill in theart would understand that the components and methods described withrespect to each respective RFID device 30 are equally applicable to RFIDdevice 30′ shown, for example, in FIG. 31.

Another embodiment of a method of enhanced protection againstunauthorized interrogation of a contactless circuiting device includespositioning a separate contactless signal capture device (e.g., RFIDsignal capture device 40, 40′) in association with a container andadjacent each separate contactless circuitry device to be protected(e.g., RFID device 30, 30′) to thereby block or otherwise preventunauthorized interrogation of the separate contactless circuitrydevice/devices, and selectively separating a separate contactlesscircuitry device from being adjacent the separate contactless signalcapture device for authorized interrogation of the separate contactlesscircuitry device. Contactless circuitry of the separate contactlesscircuitry device to be protected, for example, can be in the form ofvarious contactless devices to include RFID, Bluetooth, WI-FI, radiofrequency microwave frequency, cellular frequency, global positioningsystem, and optical/infrared (with some modifications).

Another embodiment of a method of preventing data transfer between anearby RFID reader 50 and an RFID transponder “tag” 33 containing datato be protected generally carried by an RFID device 30, 30′, can includethe steps of inductively coupling an RFID signal capture device 40, 40′,with the RFID tag 33 and the RFID reader 50 to thereby effectivelyprevent data transfer between the RFID tag 33 and the nearby RFID reader50 when the RFID signal capture device 40, 40′, is positioned by a userin close proximity to the RFID tag 33 and when the RFID reader 50 isproducing an interrogation signal (block 201). The step of preventingdata transfer can also include inductively coupling the RFID signalcapture device 40, 40′, with the RFID tag 33 when positioned in closeproximity to the RFID tag 33 and when the RFID tag 33 is producing areply to an interrogation signal. This step can also include preventingdata transfer between the RFID reader 50 and multiple protected RFIDtags 33, simultaneously, to include inductively coupling the RFID signalcapture device 40, 40′, with at least one, but preferably each of theprotected RFID tags 33 when positioned in close proximity to the RFIDtags 33, such as, for example, when placed together in a credit cardsection of a wallet/purse, etc., and when the respective RFID tags 33are being interrogated with an interrogation signal and/or producing areply to the interrogation signal.

A method can also include indicating to the user of the RFID tag 33 thatthe RFID reader 50 is attempting to interrogate the RFID tag 33 (or tags33 if multiple are being protected) when the RFID reader 50 is producingthe interrogation signal and when the RFID signal capture device 40,40′, is in close proximity to the RFID tag 33 (block 203). Accordingly,the step of indicating to the user of the RFID tag 33 that the RFIDreader 50 is attempting to interrogate the RFID tag 33 can includeilluminating a visual indicator 68 carried by the RFID signal capturedevice 40, 40′, and/or sounding an audible indicator 68 carried by theRFID signal capture device 40, 40′. Note, the RFID signal capture device40, 40′, can be configured so that such indication is not provided whenthe RFID signal capture device 40, 40′, is not in close proximity to theRFID tag 33.

The method can also include allowing data to transfer between the RFIDdevice 30, 30′, and an RFID reader 50 by selectively substantiallyseparating the RFID signal capture device 40, 40′, from being adjacentthe RFID tag 33 to allow authorized interrogation of the RFID tag 33(block 205). Accordingly, the RFID signal capture device 40, 40′, can beconfigured to not interfere with operation of the RFID reader 50 whenthe RFID signal capture device 40, 40′, is not positioned in closeproximity to an RFID tag 33. Further, according to a preferredconfiguration, the RFID signal capture device 40, 40′ is generallyadapted to provide a visual or audible indication of an interrogationsignal when positioned sufficiently close to the RFID reader 50,regardless of its position with respect to the RFID device 30, 30′.Still further, the RFID signal capture device 40, 40′, can alternativelybe configured to provide a visual or audible indication of data transferwhen the RFID signal capture device 40, 40′, is not positioned in closeproximity to the RFID tag 33 so as not to disrupt communication betweenthe RFID device 30, 30′, and the RFID reader 50 as long as the RFIDsignal capture device 40, 40′, is positioned sufficiently close to theRFID reader 50.

As shown in FIG. 34 and in FIGS. 11A-11H, a method of enhancingprotection against unauthorized interrogation of a one or more RFID datastorage devices (30, 30′) can include positioning a separate RFIDdisrupter device or RFID signal capture device (40, 40′) adjacent one ormore separate RFID data storage devices (30, 30′) (block 211). The RFIDdisruptor device includes an RFID signal disruptor circuit positioned orcontained within a container. The RFID signal disruptor circuit caninclude a transducer positioned to receive portions of the RFIDinterrogation signal and to emanate a disruptive signal, a high-speedswitch operably coupled to the transducer to provide for approximatesignal synchronization with the RFID interrogation signal to therebygenerate the disruptive signal having an insubstantial propagationdelay, and a signal ringer comprising a current regulator coupled to thehigh-speed switch to extend a duration of the disruptive signal beinggenerated.

The method can also include mutually inductively coupling the separateRFID disrupter device with the adjacent one or more separate RFID datastorage devices (30, 30′) during an attempted read by a RFIDinterrogation device (50, 50′) (block 213), receiving, by the separateRFID disrupter device, portions of an incoming signal from an RFIDinterrogation device (50, 50′) directed to the one or more separate RFIDdata storage devices (30, 30′) (block 215), generating, by the separateRFID disrupter device, a signal at substantially the same data rate asthe received incoming signal (block 217), and combining the generatedsignal with portions of the incoming signal to thereby form one or moredisrupting signals to disrupt RFID interrogation by the RFIDinterrogation device (50, 50′) during an attempt to interrogate the oneor more separate RFID data storage devices (30, 30′) (block 219). Theone or more disrupting signals form a disrupting zone extending adjacentthe one or more separate RFID data storage devices (30, 30′) to disruptthe ability of the one or more separate RFID data storage devices (30,30′) to properly communicate in response to an attempted read from anRFID interrogation device (50, 50′) when the RFID interrogation device(50, 50′) is positioned to read the one or more separate RFID datastorage devices (30, 30′) and the separate RFID disrupter device ispositioned adjacent the one or more separate RFID data storage devices(30, 30′).

The method can also include selectively separating the one or moreseparate RFID data storage devices (30, 30′) from being positionedadjacent the separate RFID disrupter device to allow authorizedinterrogation of the one or more separate RFID data storage devices (30,30′) (block 221).

In the drawings and specification, there have been disclosed a typicalpreferred embodiment of the invention, and although specific terms areemployed, the terms are used in a descriptive sense only and not forpurposes of limitation. The invention has been described in considerabledetail with specific reference to these illustrated embodiments. It willbe apparent, however, that various modifications and changes can be madewithin the spirit and scope of the invention as described in theforegoing specification. For example, the above and exemplaryembodiments generally referred to RFID transponders/tags functioning at56 MHz, it should be understood that applications according to otherfrequencies such as, for example, 900 MHz, and others, are within thescope of the present invention. Also, for example, although primarilydescribed with respect to a single RFID tag 33 on a single RFID device,applications of the RFID signal capture devices or disrupter devicesinclude those positionable to not only protect a single RFID device 30,30′ carrying a single RFID tag 33, or multiple RFID devices 30, 30′ eachcarrying a separate single independent RFID tag 33, but also single ormultiple RFID devices 30, 30′, each carrying multiple RFID tags 33,having an anti-collision protocol and/or tuned for differentfrequencies.

That claimed is:
 1. A radio frequency identification (RFID) signaldisruptor device to prevent data transfer between a nearby RFIDinterrogation device and one or more RFID data storage devices when theRFID signal disruptor device is positioned adjacent the one or more RFIDdata storage devices interrogated therewith, the RFID signal disruptordevice comprising a container, and an RFID signal disruptor circuitpositioned associated with the container and configured to disrupt anattempted read of a separate RFID data storage device by the RFIDinterrogation device when the separate RFID data storage device ispositioned adjacent the RFID signal disruptor circuit so as to allowmutual inductive coupling therebetween, the RFID signal disruptor deviceoperatively receiving power needed to operate the RFID signal disruptorcircuit from an interrogation signal emanating from the RFIDinterrogation device during the attempted read of the separate RFID datastorage device when mutually inductively coupled with the separate RFIDdata storage device, the RFID signal disruptor circuit being positionedto generate quickly an oscillating disruptive signal during theattempted read by the interrogation signal, thereby to disrupt the oneor more RFID data storage devices from communicating with the RFIDinterrogation device.
 2. The RFID signal disruptor device as defined inclaim 1, wherein the RFID signal disruptor device further includes: atransducer positioned to receive portions of the RFID interrogationsignal and to emanate a disruptive signal, a high-speed switch operablycoupled to the transducer to provide for approximate signalsynchronization with the RFID interrogation signal to thereby generatethe disruptive signal, and a current regulator coupled to the high-speedswitch to permit voltage fluctuations across the high speed switch. 3.An RFID signal disruptor device as defined in claim 1, wherein the RFIDsignal disruptor device further includes: a signal ringer comprising acurrent regulator coupled to a high-speed switch.
 4. The RFID signaldisruptor device as defined in claim 1, wherein the RFID signaldisruptor device is devoid of a permanent power storage device, relyingon energy from the RFID interrogation signal to power the RFID signaldisruptor circuit.
 5. An RFID signal disruptor device as defined inclaim 2, wherein the RFID signal disruptor device further includes avoltage regulator operably coupled to the high-speed switch and thecurrent regulator to stabilize a voltage of the high-speed switch, thevoltage regulator including a resistor positioned to stabilize voltageof the transistor to thereby provide for substantially consistentoperation of the transistor over a range of voltages; wherein theinductor is a wound inductor connected between the emitter or drain ofthe transistor and a first end of the resistor, wherein a second end ofthe resistor is connected to a base or gate of the transistor, andwherein the RFID antenna is connected between a collector or source ofthe transistor and a second end of the resistor; and wherein analternating current (AC) capacitor is connected between the first andthe second ends of the resistor.
 6. An RFID signal disruptor device asdefined in claim 2, wherein the RFID signal disruptor circuit furtherincludes: a frequency regulator operably coupled to the high-speedswitch to control frequency characteristics of the disruptive signal. 7.An RFID signal disruptor device as defined in claim 6, wherein the RFIDsignal disruptor circuit further includes: a visual operation indicatorcoupled to the high-speed switch to provide a visual indication that theRFID interrogation device is attempting to interrogate the separate RFIDdata storage device when the RFID signal disruptor circuit is positionedin close proximity to the separate RFID data storage device, sufficientto allow mutual inductive coupling therebetween, when the RFIDinterrogation device is producing an interrogation signal withinactivation range of the separate RFID data storage device.
 8. An RFIDsignal disruptor device as defined in claim 6, wherein the RFID signaldisruptor circuit further includes: a voltage regulator operably coupledto the high-speed switch and the current regulator to stabilize avoltage of the high-speed switch.
 9. An RFID signal disruptor device asdefined in claim 6, wherein the RFID signal disruptor circuit comprises:a frequency regulator operably coupled to the high-speed switch tocontrol frequency characteristics of the disruptive signal, thefrequency regulator comprising a diode positioned to provide harmonicmultiplication of the frequency of the interrogation signal; and whereinthe diode is connected between the base and the emitter of a transistor.10. A method of enhancing protection against unauthorized interrogationof one or more RFID data storage devices, the method being characterizedby the steps of: positioning a separate RFID signal disrupter deviceadjacent one or more separate RFID data storage devices, the RFIDdisruptor device including an RFID signal disruptor circuit beingpositioned to generate quickly an oscillating disruptive signal duringan attempted read by an interrogation signal, thereby to disrupt the oneor more RFID data storage devices from communicating with the RFIDinterrogation device; mutually inductively coupling the separate RFIDsignal disrupter device with the one or more separate RFID data storagedevices during an attempted read by an RFID interrogation device;receiving at least portions of an incoming signal from an RFIDinterrogation device directed to the one or more separate RFID datastorage devices; and generating a signal to disrupt the attempted readby the RFID interrogation device.
 11. The method of claim 10, furthercomprising: combining the generated signal with portions of the incomingsignal to thereby form one or more disrupting signals to disrupt RFIDinterrogation by the RFID interrogation device during an attempt tointerrogate the one or more separate RFID data storage devices, the oneor more disrupting signals forming a disrupting zone extending adjacentthe one or more separate RFID data storage devices to disrupt theability of the one or more separate RFID data storage devices toproperly communicate in response to an attempted read from an RFIDinterrogation device when the RFID interrogation device is positioned toread the one or more separate RFID data storage devices and the separateRFID signal disrupter device is positioned adjacent the one or moreseparate RFID data storage devices.
 12. The method of claim 10, furthercomprising: selectively separating the one or more separate RFID datastorage devices from being positioned adjacent the separate RFID signaldisrupter device to allow authorized interrogation of the one or moreseparate RFID data storage devices.
 13. The method of claim 10, furthercomprising: controlling frequency characteristics of the signal via afrequency regulator, the frequency regulator providing harmonicmultiplication of the frequency of the incoming signal.